In the current Internet and communication applications, the address book information (also called contact information) of a user may be distributed in several places, e.g., information on the user or his/her friends may be found in mobile phones, Emails, Taobao, etc. Since the expansion of information, the address book information will include not only traditional information like name, age, address, telephone number, but also email address, micro-blog address, etc. All or part of the information is keyed in manually by the user and the user needs to key in the information all over again every time the user registers at a new website; and when the information of a friend changes, the user also needs to make amendments manually.
Along with the growth of Internet applications, more and more applications are coming up, such as QQ, micro-blogs, Internet communities, ecommerce applications, etc. Every application has its own address book and the more and more information is included in the address book, and thus maintaining the information and keeping the information consistent with the actual situation has become a heavy burden.